Jus Herbs wrote:We'll have a solution for legal partnership before we leave Spain, so we're not so concerned about proving the relationship.
So regardless of our relationship status I'll need a visa first? Or if we have a legal relationship then I can just go with him and get the residence permit when we're there?
Based on my knowledge:
If you have a legal relationship and a Spanish residence permit as his spouse, then I assume you can move here, and apply for a residence permit along with him when he registers here in local townhall/commune.
If you have a legal partnership, but still on your student visa, then you may need a D type visa for long-stay in Belgium and registering as his spouse/dependent.
Again, this is based on my knowledge. For an official answer, you may write to the Belgian consulate in Spain.